Carton packaging machine

ABSTRACT

A carton-packaging machine (10) which causes progressive erection of carton sleeves from a supply of blanks (11) in a magazine (19), the partly erected blanks being loaded with product (24, 25) and then being closed in the form of a sleeve around the product. An endless conveyor (12) moves the blank through a blank supply station (14), an erection station (15), a product loading stations (16), a folding station (17) and a discharge stations (18), and a suction device (20) cooperates with the magazine (19) in order to draw individual blanks in flat form into the path of travel of the conveyor (12) for engagement thereby. A shaping device (21) at the erection station (15) forms each blank into U-shaped form and which is then advanced by the conveyor to the loading station (16) for loading with product (24, 25). Overhead folding rods (34, 35, 36) at the folding station (17) engage the upper portions (25a, 23b ) of the side flaps (23) of the blank in order to fold the side flaps inwardly into overlapping relation, with a line of adhesive therebetween, in order to complete the formation of the carton sleeve.

This invention relates to a carton packaging machine which is operableto cause progressive erection of carton-forming blanks, to permitloading of the partly erected blanks with product, to complete theformation of each carton and to close the latter with the productlocated therein, and to discharge each closed carton from the machine.

The invention is particularly concerned with a machine for use informing carton sleeves, such machines being known as "sleevingmachines". In machines of this type, a stack of blanks is supplied tothe machine, and the blanks are fed singly to the machine and thenundergo progressive erection, loading with product, final formation intosleeve form, and then discharge of the sleeved product.

Existing designs of sleeving machine wrap the blank around the productby drawing the blank downwardly onto the top of the product and byfolding sides of the blank downwardly so as to lie alongside theproduct, and then by folding the lower margins of the side of the blankunder the product, followed by sealed closure. This manipulation of theblank is somewhat complicated, and it is a particularly difficult partof the operation to ensure that the blank is folded under the productand then secured by adhesive in a satisfactory manner.

In the known machine, the wrapping of the blank around the product isdone entirely by the machine, and any incorrect initial positioning ofthe product, or improper presentation of the blank to the product,cannot be corrected manually by an operator, and the machine istherefore liable to form sleeved packaging which is not alwayssatisfactory, and particularly does not hold the product securely, ifthe bottom closing and sealing operation has not been completedsatisfactorily.

There are standard tests for packaging, one of which requires that thepackaging should not be damaged, and neither should the product becomeloose or dislodged, following dropping of the packaging from a standardheight onto a hard surface. Existing designs of sleeving machine do notalways achieve a satisfactory and repeatable operating performance inthe formation of sleeve cartons, such as to meet the standard tests.

The invention therefore seeks to provide a carton packaging machinewhich handles the blanks in a different way, such that more readilyrepeatable sleeve closure of the blank around a product can be achieved.

According to the invention there is provided a carton-packaging machinewhich is operable to cause progressive erection of carton sleeves from asupply of blanks, to permit loading of partly erected blanks withproduct, to complete the formation of a sleeve around each product andto close the latter with the product located therein, and to dischargethe loaded sleeve from the machine, in which the machine comprises:

an endless conveyor movable progressively through a blank-supplystation, an erection station, a product-loading station, a foldingstation, and a discharge station;

a magazine arranged at the blank-supply station for holding a stack ofblanks;

a suction device arranged to co-operate with the magazine and to operatein timed sequence with the operation of the conveyor in order to engageand to draw blanks individually in turn, in flat form, into the path oftravel of the conveyor for engagement thereby;

a shaping device arranged at the erection station and engageable by eachblank in order to form the blank into a U-shape having a base and a pairof side flaps extending upwardly from the base, each U-shaped blankbeing then advanced by the conveyor to the loading station at whichproduct can be loaded onto the base; and

a folding device arranged at the folding station above the conveyor andengageable with the upper portion of the side flaps, as each loadedblank is advanced to the folding station, so as to fold the side flapsinwardly into overlapping relation in order to complete the formation ofthe carton sleeve.

The packaging machine according to the invention operates to form cartonsleeves in a novel manner, in that the product can be loaded downwardlyinto the partly erected cartons, and this permits the product to belocated in desired positions readily especially when, as is preferred,loading takes place by hand.

The formation of the carton sleeve is thus completed by inwardly foldingthe side flaps over the top of the product, and this operation is muchmore readily carried out in a satisfactory and repeatable manner, thanby the known technique of underside closure.

Permanent closure of each carton sleeve may take place in any convenientmanner, such as by providing pre-formed adhesive strips on one or bothof the side flaps of each blank. However, it is preferred that sealedclosure takes place by arranging an adhesive applicator so as toco-operate with the folding device in order to form a line of adhesiveon the underlying one of the overlapping side flaps, prior to finalpressing-down of the uppermost flap.

One preferred adhesive applicator comprises a hot melt adhesive jettingdevice which delivers, in timed sequence, a line of adhesive which hasthe property of forming a permanent closure fairly rapidly i.e. by thetime the carton sleeve has left the folding station and is on its way tothe discharge station.

In order to achieve an orderly supply of blanks, one by one, into thepath of the conveyor, it is preferred to arrange the magazine so that ishas two separate guide portions, a first of which extends substantiallyvertically upwardly from the path of travel of the conveyor, and asecond of which extends upwardly and rearwardly with respect to thedirection of travel of the conveyor. By this arrangement of themagazine, the blanks undergo relative longitudinal displacement as theydescend through the second guide part to the first guide part, and thisfeature assists in the separation of the blanks so as to prevent themfrom adhering to each other by friction, partial vacuum, or boardinterlocking so that they can readily be discharged one by one from thefirst guide part into the path of travel of the conveyor.

In order to advance the blanks through the various operating stations ina reliable manner, it is preferred that the conveyor takes the form of aslatted conveyor having upwardly projecting flights spaced apart alongthe length of the conveyor.

Preferably, rails extend alongside and above the upper run of theconveyor, the rails serving to support the base of the carton-blank asit undergoes erection during travel along the conveyor.

The carton sleeves will be shaped into any suitable form, according tothe type of product which is to be loaded therein. By way of exampleonly, product which can be loaded in the sleeves include cans, such astins of cat food, foil packed product, such as jam sponges, and plasticcontainers, such as yoghurt packs. The product may comprise singleitems, each contained in its own sleeved carton, or a series of productmay be loaded into each carton. Indeed, in a preferred arrangement, twotier arrangements of product may be arranged in each carton sleeve.

An embodiment of carton-packaging machine according to the inventionwill not be described in detail, by way of example only, with referenceto the accompanying drawings, in which:

FIG. 1 is a diagramatic side view of a sleeve-forming packaging machineaccording to the invention;

FIGS. 2a and 2d show successive stages in the erection and closure of acarton sleeve by the machine;

FIG. 3 is a transverse view of the upstream end of the machine, adjacentto a magazine for supplying blanks to the machine;

FIG. 4 is a transverse view near to the downstream end of the machine,and showing the initial part of the final stage of carton formation;

FIG. 5 is a transverse view of the downstream end of the machine showingthe final stage of carton formation; and,

FIG. 6 is a plan view showning guide rods for deforming the upwardlyprojecting sides of the blank during the final stages.

Referring now to FIG. 1 of the drawings, a carton-packaging machineaccording to the invention is designated generally by reference 10, andwhich is operable to cause progressive erection of a carton sleeve froma blank 11, as shown in FIG. 2a, to permit loading of partly erectedblanks with product, as shown in FIGS. 2b and c, to complete theformation of the sleeve around the product, as shown in FIG. 2d, and toclose the carton sleeve with the product located therein, and todischarge the loaded sleeve to a discharge station.

The machine 10 comprises an endless conveyor 12 in the form of a slattedconveyor having upwardly extending flights 13 which serve to advanceeach blank 11 through its various treatment stations. The slattedconveyor 12 runs below a pair of horizontally spaced rails 12a (seeFIGS. 3, 4 and 5) on which the blank is supported during its movement bythe conveyor from one station to another while appropriate action takesplace at each station. Thus, as shown in FIG. 1, the upper run of theconveyor 12 is movable progressively through a carton blank-loadingstation 14, an erection station 15, a product-loading station 16, afolding station 17 and a discharge station 18.

A magazine 19 is arranged at the station 14 for holding a stack ofblanks 11, and a suction device 20 is arranged to co-operate with themagazine 19 and to operate in timed sequence with the operation of theconveyor 12 in order to engage and to draw blanks 11 individually inturn, in flat form, into the path of travel of the flights 13 of theconveyor 12 for engagement thereby.

A plough shaped forming device 21 (shown only diagramatically in FIG. 1)is arranged at the erection station 15 so as to be engaged by each flatblank 11 as it is advanced by the conveyor 12 to the station 15, andoperates in order to form the blank into a U-shape. The forming device21 is a plough-type device known per se in the erection of cartons fromblanks, and it causes the blanks to fold upwardly about fold lines 22a(see FIGS. 2a to 2d) extending alongside a base 22, and so as to formtwo upwardly extending side flaps 23.

FIG. 2d shows the blank 11 is partly erected form, and also shows aproduct container 24 thereon. However, the loading of the erected blankwill only take place after advancement of the blanks by the conveyor 12to the loading station 16. This loading can take place by automaticproduct-feeding devices (not shown), or by manual insertion of theproduct by one of more operators standing at the station 16.

The product is particularly suitable for loading and location inposition, since it has an essentially stable shape.

FIG. 2b shows a single product 24 in the partly erected blank, but twoor more products can be loaded in a single row on the base 22. The sideflaps 23 can then be retained in position by folding-over the edge flaps23a and 23b about fold lines 23¹ and adhesively securing together theedge flaps at station 17.

A single row or layer of product can be loaded into the partly erectedcarton of FIG. 2b, but it two layers of product are required, then aspacer plate 24a can be fitted, as shown in FIG. 2c, which forms a baseonto which a further layer of product can be loaded, as shown in FIG.2c. The closure of the carton can be as just described, and alongitudinal restraint to movement of the product is obtained byengagement of projecting portions of the lower rims of the product 24and 25 through cut-outs 26 and 27 formed in the side walls of the blank.

A folding device 26 is arranged at the folding station 17 and above theconveyor 12, this being engaged by the upper portion of the side flaps23, as the loaded partly-erected carton sleeves are advanced to thestation 17, so as to fold the upper margins of the side flaps 23inwardly into overlapping relation in order to complete the formation ofthe carton sleeve, as shown in FIG. 2d. An adhesive applicator in theform of a hot jet adhesive applicator 27 is arranged to co-operate withthe folding device 26, and applies a line of hot melt adhesive on theunderlying side flap 23a of the top closure of the sleeve, the uppermostside flap 23b being pressed down onto the line of adhesive during thefinal stages of treatment of the carton sleeve by the folding device 26as it leaves the latter prior to passage to a discharge chute 31 at thedischarge station 18.

In order to achieve an orderly supply of blanks 11, one by one, into thepath of the flights 13 of the conveyor 12, the magazine 19 has twoseparate guide portions, in which a first guide portion 32 extendssubstantially vertically upwardly from the path of travel of theconveyor 12, and a second guide part 33 extends upwardly and rearwardlywith respect to the direction of travel of the conveyor. By thisarrangement of the magazine, the blanks 11 undergo relativelongitudinal/horizontal displacement as they descend through the secondguide part 33 to the first guide part 32, and this feature assists inthe separation of the blanks so as to prevent adhesion (by friction,partial vacuum, or board interlocking) between them, whereby they can bereadily discharged, one by one, from the first guide part 32 into thepath of travel of the flights 13 by downward movement of the suctionheads 20.

FIG. 3 shows in more detail the initial formation of each blank, whichis drawn downwardly from the magazine 19 and is then moved along theupper run of the conveyor 12 by one of the flights 13 into engagementwith the forming device 21, which takes the form of an invertedgenerally U-shaped box member 32. The lower edge 33 of the member 32tapers so as to approach the rails 12a, in the direction of motion ofthe upper run of the conveyor, so as to cause the base 22 of the blankto approach progressively the rails 12a (the lowest part of edge 33 isshown by reference 33 prime). During this downward and forward movementof the base 22 the side flaps pivot upwardly, and this may be furtherassisted by guide bars, rods or plates (not shown) alongside the member32, which forms a type of "folding box". The now U-shaped and partlyerected carton is now delivered to the loading station 16 to haveproduct loaded therein. After completion of product loading, thepartly-erected carton then travels to the final closing station 17,which is shown in more detail in FIGS. 4, 5 and 6.

As shown in FIGS. 4 and 5, the side flaps 23 are guided by guides 34, 35and 36 so as to be brough closer to each other for the final closingoperation, which first folds the shorter edge flap 23a downwardly to theposition shown in dotted lines in FIG. 5, so as to be ready to receivean adhesive strip from applicator 27, and then the longer edge flap 23bis folded downwardly to the dotted position in order to complete theclosure of the carton, ready for discharge down the chute 31. To assistthe final closing action, a horizontal guide plate may be arranged (notshown) to press the edge strips 23a and 23b together in the horizontalposition.

The embodiment of sleeving machine is particularly suitable for themedium-speed packaging of foil, tin-plated cans, plastics containers,pots, tubs and trays, in a one×two, one×three, one×four to two on twoconfiguration, as desired. The machine functions automatically to wrap asuitable carton sleeve around the product.

Product containers having a diameter or width in the range 64millimetres to 134 millimetres, and product height of 25 millimetres to114 millimetres can be handled, and the length of the carton sleeve canbe from 64 millimetres to 340 millimetres. It should be understood thatthese are only examples, and that sizes outside these ranges may also beacceptable subject, if necessary, to minor machine modifications. Thespeed of the machine can be selected from 11 to 55 sleeves per minute,though speed outside this range may be available subject to machinelength for loading/number of operators required/pitch of machine/sleevelength.

The magazine can hold approximately 500 to 1000 sleeve blanks, dependingupon the calibre of the blanks, with automatic vacuum pick-off andplacement of the blanks into the flights of the slatband conveyor 12.The folding unit 21 is referred to as a "folding box unit", which isable to fold a flat blank into a U-shaped section. A length of about1700 millimetres can be made available at the loading station 16, fortwo operators to load the partly erected containers with product.Although not shown in detail in FIG. 1, the folding unit 26 includes anoverhead ploughing unit to partially fold the side flaps of the sleeveover the containers, and this is followed by hot melt jetting via theadhesive applicator 27, followed by final closure of each carton sleeveby an overhead compression unit (not shown) provided in the foldingdevice 26, prior to discharge of the fully packed carton sleeves.

MACHINE OPERATION

Prior to start-up, the magazine is filled with flat blanks, and the hotmelt jetting unit is brough up to temperature. Product containers aremade available along one side of the machine, either on a conveyor or inbulk trays arranged on an inclined stand, and the operators arepositioned so as to be able to pick up and place the product containersin the partly erected blanks. As the machine is running, blanks can befed from the magazine at the discretion of the operator, or can be leftto run continuously by switching-on or off a vacuum control valve. Asthe blanks issue from the magazine, they are folded into a U-shapedsection and pass in front of the operator who places the productcontainers into the U-shaped sleeves. As the sleeves pass down the line,they are wrapped around the containers, and are held by means of hotmelt jetting, prior to going through the overhead compression unit todischarge.

The folding unit 26, shown diagramatically only in FIG. 1, is a staticunit, but it may be desirable to provide moveable carriage type guidesand folders, which travel alongside the moving sleeve, in order to exerta particularly reliable, and readily repeatable inward folding andpressing action on the sleeves.

A further advantage of the inclined stacking provided by the magazine isthat it reduces the effect of the full load of the stack of blanks onthe bottom blank which is about to be withdrawn by the suction unit.

For product loading onto the bases 22 on the blanks, the product willnormally be inverted with the closure tops facing downwardly (andprojecting laterally through the cut-outs in the side walls). The partlyerected blank will then travel along the guide rails 12a above the slatband conveyor 12.

However, for other types of product, it may be preferably for holes tobe formed in the bases 22, through which the bases of tapering pots canextend so as to be supported directly by the slat band conveyor 12. Thepots are then retained in position by a generally similar foldingoperation of the blank as described previously, but the pots are heldcaptive against longitudinal movement by being seated in the holes inthe bases 22.

If so-called double "lane" filling of carton sleeves is required,suitably larger blanks with pre-formed fold lines may be provided, withcorresponding enlargement in width of the magazine, and the conveyortrack and the folding device co-operating therewith, so as to form awrap-around carton sleeve engaging two lanes of product i.e. side byside rows of product in one or two layers or tiers if required.

I claim:
 1. A carton-packaging machine which is operable to causeprogressive erection of carton sleeves from a supply of blanks, topermit loading of partly erected blanks with product, to complete theformation of a sleeve around each product and to close the latter withthe product located therein, and to discharge the loaded sleeve from themachine, in which the machine comprises;an endless conveyor moveableprogressively through a blank-supply station, an erection station, aproduct-loading station, a folding station, and a discharge station; amagazine arranged at the blank-supply station for holding a stack ofblanks; a suction device arranged to co-operate with the magazine and tooperate in timed sequence with the operation of the conveyor in order toengage and draw blanks individually in turn, in flat form, into the pathof travel of the conveyor for engagement thereby; a shaping devicearranged at the erection station and engageable by each blank in orderto form the blank into a U-shape having a base and a pair of side flapsextending upwardly from the base, each U-shaped blank being thenadvanced by the conveyor to the loading station at which product can beloaded onto the base; and a folding device arranged at the foldingstation above the conveyor and engageable with the upper portion of theside flaps, as each loaded blank is advanced to the folding station, soas to fold the side flaps inwardly into overlapping relation in order tocomplete the formation of the carton sleeve; and rails extendingalongside and above the upper run of the conveyor, the rails serving tosupport the base of the blank as it undergoes erection during travelalong the conveyor.
 2. A machine according to claim 1 in which theconveyor takes the form of a slatted conveyor having upwardly projectingflights spaced apart long the length of the conveyor.
 3. A machineaccording to claim 1, including an adhesive applicator arranged toco-operate with the folding device in order to form a line of adhesiveon the underlying one of the overlapping side flaps, prior to finalpressing-down of the uppermost flap.
 4. A machine according to claim 3,in which the adhesive applicator comprises a hot melt adhesive jettingdevice arranged to deliver, in timed sequence, a line of adhesive on theunderlying side flap.
 5. A machine according to claim 1 in which themagazine comprises a first guide portion which extends substantiallyvertically upwardly from the path of travel of the upper run of theconveyor, and a second guide portion which extends upwardly andrearwardly with respect to the direction of travel of the conveyor.